Outline Of Electrical Circuitry - Canon PC920 Service Manual

CHAPTER 2 BASIC OPERATION
B.

Outline of Electrical Circuitry

The machine's major electric mechanisms are controlled by the microprocessor mounted on
the DC controller PCB, which reads input signals from sensors and operating keys according to the
instructions of the program stored in advance and sends signals used to drive motors, solenoids,
lamps, and other loads as needed.
<Sensor Block>
Sensor
• Scanner home position detection
• Lens home position detection
• Pre-registration roller paper
detection
• Delivery paper detection
• Vertical path roller paper detection
• Single-feeder paper detection
AE sensor
PCB
Thermistor
• Scanner thermistor
• Fixing thermistor
Control
panel
Power
switch
Sensor/
switch
2-2
<Control Block>
DC controller PCB
Q101
CPU
+5V
+24V
ADF
Figure 2-102
COPYRIGHT © 1999 CANON INC.
<Loads>
Composite
power supply PCB
Scanning lamp
Q900
CPU
High-
Contact
voltage
PCB
circuit
block
• Pickup clutch solenoid
• Registration clutch solenoid
Solenoid • Lens solenoid
• Multifeeder pickup solenoid
• Cassette pickup solenoid
Side blanking
lamp
Scanner/
lens drive motor
Scanner cooling fan
ADF load
CANON PC800s/900s REV.0 AUG. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
Fixing heater
• Primary charging roller
• Developing cylinder
• Transfer charging roller
• Static eliminator
Main motor Main
driver PCB motor